JP4777077B2 - Functional element - Google Patents

Description

  The present invention relates to a functional element. In particular, the present invention relates to functional elements such as organic electroluminescent elements, inorganic electroluminescent elements, and photoelectric conversion elements.

In recent years, various functional elements have been developed and proposed. For example, an element that emits light by passing an electric current, such as an organic electroluminescence element and an inorganic electroluminescence element, or a photoelectric conversion element that generates power by irradiating light is known.
In particular, organic electroluminescent devices using thin-film materials that emit light when excited by electric current can emit light with high brightness at low voltage, so mobile phone displays, personal digital assistants (PDAs), computer displays, automobiles It has a wide range of potential uses in a wide range of fields including information displays, TV monitors, or general lighting, and has advantages such as thinning, weight reduction, miniaturization, and power saving of devices in these fields. For this reason, the expectation as a leading role of the future electronic display market is great. However, in order to be practically used in place of conventional displays in these fields, many technical improvements such as light emission luminance and color tone, durability under wide usage environment conditions, low cost and mass productivity are problems. Yes.

There is a demand for an organic electroluminescent element of a linear light source. For example, a linear organic light source using a strip electrode as a white light source (for example, see Reference 1) for a liquid crystal backlight or an image sensor, or a light source for scanning exposure or image reading (for example, see Reference 2). An electroluminescent device is disclosed. However, in the former structure of the white light source, when the upper electrode is thinned, there is a risk that the upper electrode is cut and short-circuited by the unevenness of the striped lower electrode. In the latter structure of the light source for scanning exposure or image reading, a structure is adopted in which a lead wire is provided in each stripe unit to prevent a short circuit, but this is a preferable structure in the case of a linear light source with a small number of stripes. However, reading a fine image requires a large number of narrow stripes for exposure, and it is not easy to attach lead wires for taking out all of them.
JP 2003-51380 A Japanese Patent Laid-Open No. 2005-260821

  An object of the present invention is to provide a functional element that is excellent in manufacturing suitability and excellent in resistance to disconnection failure, and particularly to provide an improved organic electroluminescent element and inorganic electroluminescent element.

The above-described problems of the present invention have been solved by the following means.
<1> A first electrode in which a plurality of stripe electrodes are arranged in parallel on a substrate, a second electrode terminal arranged on the same plane as the first electrode in which the plurality of stripe electrodes are arranged in parallel, and arranged opposite to the first electrode A second electrode connected to a terminal of the second electrode, and a functional element having a functional layer sandwiched between the first electrode and the second electrode,
In the both end portions of the first stripe electrode longitudinally disposed between the area corresponding to the functional area of the terminal portion of the first electrode on the first electrode, SL before the gap between the stripe A flattening insulating layer that fills thicker than the thickness of the first electrode and covers and flattens a part of the first electrode and the second electrode terminal ;
The second electrode is arranged in a planar shape having a uniform thickness so as to cover the region corresponding to the functional region on the first electrode and the planarization insulating layer, and is connected to the second electrode terminal.
The functional element, wherein the functional layer on the planarization insulating layer is insulated from the first electrode at an end in the longitudinal direction.
<2> The functional element according to <1>, wherein the functional layer forms a continuous layer at an end in the longitudinal direction.
<3> The functional element according to <1> or <2>, wherein the planarization insulating layer is formed of a photosensitive resin or a thermosetting resin.
<4> The functional element according to any one of <1> to <3>, wherein an inorganic insulating layer is provided between the planarizing insulating layer and the functional layer.
<5> The functional element according to any one of <1> to <4>, wherein at least one of the functional layers is a light emitting layer.
<6> The functional element according to <5>, wherein the functional element is an organic electroluminescent element.
<7> The functional element according to <5>, wherein the functional element is an inorganic electroluminescent element.

  The present invention provides a functional device that is excellent in manufacturing suitability and excellent in resistance to disconnection failure. Particularly improved organic electroluminescent devices and inorganic electroluminescent devices are provided.

The functional element of the present invention includes a first electrode in which a plurality of stripe electrodes are arranged in parallel on a substrate, a second electrode terminal arranged on the same plane as the first electrode in which the plurality of stripe electrodes are arranged in parallel, the first electrode, A second electrode connected to a terminal of the second electrode, and a functional element having a functional layer sandwiched between the first electrode and the second electrode, wherein the stripes of the first electrode At both ends in the longitudinal direction, the first electrode is disposed between the terminal portion of the first electrode and the region corresponding to the functional region on the first electrode, and the gap between the stripes is filled thicker than the thickness of the first electrode. And a planarization insulating layer that covers and planarizes the first electrode and a part of the second electrode terminal, and the second electrode corresponds to a functional region on the first electrode. And a uniform thickness so as to cover the planarization insulating layer. That is connected to the flat shape are stacked the second electrode terminal, in the longitudinal direction of the end portion, characterized in that the functional layer in the planarization insulating layer is insulated from the first electrode And
More preferably, the functional layer forms a continuous layer at the end in the longitudinal direction.
The planarization insulating layer is preferably formed of a photosensitive resin or a thermosetting resin. Preferably, an inorganic insulating layer is provided between the planarization insulating layer and the functional layer.

  As a functional layer in the present invention, light emission or distortion is generated by applying a voltage or current, voltage or current is generated by applying visible light or X-ray irradiation or pressure, and a resistance value changes due to a change in atmosphere. And the like. Specific examples include an organic electroluminescent layer, an inorganic electroluminescent layer, a photoelectric conversion layer, a piezoelectric layer, a gas detection layer, and the like. More preferred functional layers in the present invention are an organic electroluminescent layer, an inorganic electroluminescent layer, and a photoelectric conversion layer.

1. Organic electroluminescent device The organic electroluminescent device according to the present invention includes conventionally known organic compound layers such as a hole transport layer, an electron transport layer, a block layer, an electron injection layer, and a hole injection layer in addition to the light emitting layer. You may have.

Details will be described below.
1) Layer structure <Electrode>
At least one of the pair of electrodes of the organic electroluminescent element of the present invention is a transparent electrode, and the other is a back electrode. The back electrode may be transparent or non-transparent.
<Configuration of organic compound layer>
There is no restriction | limiting in particular as a layer structure of the said organic compound layer, Although it can select suitably according to the use and objective of an organic electroluminescent element, It is formed on the said transparent electrode or the said back electrode. preferable. In this case, the organic compound layer is formed on the front surface or one surface on the transparent electrode or the back electrode.
There is no restriction | limiting in particular about the shape of a organic compound layer, a magnitude | size, thickness, etc., According to the objective, it can select suitably.

Specific examples of the layer configuration include the following, but the present invention is not limited to these configurations.
Anode / hole transport layer / light emitting layer / electron transport layer / cathode,
Anode / hole transport layer / light emitting layer / block layer / electron transport layer / cathode,
Anode / hole transport layer / light emitting layer / block layer / electron transport layer / electron injection layer / cathode,
Anode / hole injection layer / hole transport layer / light emitting layer / block layer / electron transport layer / cathode,
Anode / hole injection layer / hole transport layer / light emitting layer / block layer / electron transport layer / electron injection layer / cathode.

Each layer will be described in detail below.
2) Hole transport layer The hole transport layer used in the present invention contains a hole transport material. The hole transport material is not particularly limited as long as it has either a function of transporting holes or a function of blocking electrons injected from the cathode. As the hole transport material used in the present invention, any of a low molecular hole transport material and a polymer hole transport material can be used.
Specific examples of the hole transport material used in the present invention include the following materials.

Carbazole derivatives, triazole derivatives, oxazole derivatives, oxadiazol derivatives, imidazole derivatives, polyarylalkane derivatives, pyrazoline derivatives, pyrazolone derivatives, phenylenediamine derivatives, arylamine derivatives, amino-substituted chalcone derivatives, Styryl anthracene derivative, fluorenone derivative, hydrazone derivative, stilbene derivative, silazane derivative, aromatic tertiary amine compound, styrylamine compound, aromatic dimethylidene compound, porphyrin compound, polysilane compound, poly (N-vinylcarbazole) derivative , Aniline copolymer, thiophene oligomer, conductive polymer oligomer such as polythiophene, polythiophene derivative, polyphenylene derivative, polyphenylene vinylene derivative, and polyphenylene Polymeric compounds such as orange derivatives.
These may be used alone or in combination of two or more.

  The thickness of the hole transport layer is preferably 10 nm to 200 nm, and more preferably 20 nm to 80 nm. If the thickness exceeds 200 nm, the driving voltage may increase. If the thickness is less than 10 nm, the light emitting element may be short-circuited, which is not preferable.

3) Hole injection layer In the present invention, a hole injection layer can be provided between the hole transport layer and the anode.
The hole injection layer is a layer that facilitates injection of holes from the anode into the hole transport layer, and specifically, a material having a small ionization potential is preferably used among the hole transport materials. For example, a phthalocyanine compound, a porphyrin compound, a starburst type triarylamine compound, etc. can be mentioned, It can use suitably.
The thickness of the hole injection layer is preferably 1 nm to 30 nm.

4) Light emitting layer The light emitting layer used in the present invention contains at least one kind of light emitting material, and may contain a hole transport material, an electron transport material, and a host material as necessary.
The light emitting material used in the present invention is not particularly limited, and either a fluorescent light emitting material or a phosphorescent light emitting material can be used. A phosphorescent material is preferred from the viewpoint of luminous efficiency.

  Examples of the fluorescent light-emitting material include benzoxazole derivatives, benzimidazole derivatives, benzothiazole derivatives, styrylbenzene derivatives, polyphenyl derivatives, diphenylbutadiene derivatives, tetraphenylbutadiene derivatives, naphthalimide derivatives, coumarin derivatives, perylene derivatives, perinone derivatives, oxalates. Diazole derivatives, aldazine derivatives, pyralidine derivatives, cyclopentadiene derivatives, bisstyrylanthracene derivatives, quinacridone derivatives, pyrrolopyridine derivatives, thiadiazolopyridine derivatives, styrylamine derivatives, aromatic dimethylidene compounds, 8-quinolinol derivative metal complexes and rare earths Various metal complexes represented by complexes, polythiophene derivatives, polyphenylene derivatives, polyphenylene vinylene derivatives, and polymers Polymeric compounds such as fluorene derivatives. These can be used alone or in combination of two or more.

  Although it does not specifically limit as a phosphorescence-emitting material, An ortho metalated metal complex or a porphyrin metal complex is preferable.

  The ortho-metalated metal complex includes, for example, Akio Yamamoto, “Organic Metal Chemistry: Fundamentals and Applications”, pages 150 to 232; Yersin's “Photochemistry and Photophysics of Coordination Compounds”, 71-77, 135-146, Springer-Verlag (published in 1987), etc. The use of the orthometalated metal complex as a light emitting material in the light emitting layer is advantageous in terms of high luminance and excellent light emission efficiency.

  There are various ligands that form the ortho-metalated metal complex, which are also described in the above documents. Among them, preferred ligands include 2-phenylpyridine derivatives, 7,8- Examples include benzoquinoline derivatives, 2- (2-thienyl) pyridine derivatives, 2- (1-naphthyl) pyridine derivatives, and 2-phenylquinoline derivatives. These derivatives may have a substituent if necessary. The orthometalated metal complex may have other ligands in addition to the above ligands.

The orthometalated metal complex used in the present invention can be obtained from Inorg Chem. 1991, 30, 1685, 1988, 27, 3464, 1994, 33, 545, Inorg. Chim. Acta, 1991, No. 181, page 245; Organomet. Chem. 1987, No. 335, 293, J. Am. Am. Chem. Soc. It can be synthesized by various known techniques such as 1985, No. 107, page 1431.
Among the ortho-metalated complexes, compounds that emit light from triplet excitons can be suitably used in the present invention from the viewpoint of improving luminous efficiency.

Of the porphyrin metal complexes, a porphyrin platinum complex is preferred.
A phosphorescent material may be used alone or in combination of two or more. Further, a fluorescent material and a phosphorescent material may be used at the same time.

  The host material is a material having a function of causing energy transfer from the excited state to the fluorescent light-emitting material or the phosphorescent light-emitting material, and as a result, causing the fluorescent light-emitting material or the phosphorescent light-emitting material to emit light.

The host material is not particularly limited as long as it is a compound capable of transferring exciton energy to the light emitting material, and can be appropriately selected according to the purpose. Specifically, a carbazole derivative, a triazole derivative, an oxazole derivative, Oxadiazole derivatives, imidazole derivatives, polyarylalkane derivatives, pyrazoline derivatives, pyrazolone derivatives, phenylenediamine derivatives, arylamine derivatives, amino-substituted chalcone derivatives, styrylanthracene derivatives, fluorenone derivatives, hydrazone derivatives, stilbene derivatives, silazane derivatives, aromatic Tertiary amine compounds, styrylamine compounds, aromatic dimethylidene compounds, porphyrin compounds, anthraquinodimethane derivatives, anthrone derivatives, diphenylquinone derivatives, thiopi Dioxide derivatives, carbodiimide derivatives, fluorenylidenemethane derivatives, distyrylpyrazine derivatives, heterocyclic tetracarboxylic anhydrides such as naphthaleneperylene, phthalocyanine derivatives, metal complexes of 8-quinolinol derivatives, metal phthalocyanines, benzoxazoles and benzothiazoles Various metal complexes represented by ligand metal complexes, polysilane compounds, poly (N-vinylcarbazole) derivatives, aniline copolymers, thiophene oligomers, conductive polymer oligomers such as polythiophene, polythiophene derivatives, polyphenylene derivatives , Polymer compounds such as polyphenylene vinylene derivatives and polyfluorene derivatives. These compounds may be used individually by 1 type, and may use 2 or more types together.
As content in the light emitting layer of a host material, 0 mass%-99.9 mass% are preferable, More preferably, they are 0 mass%-99.0 mass%.

5) Block layer In this invention, a block layer can be provided between a light emitting layer and an electron carrying layer. The block layer is a layer that suppresses the diffusion of excitons generated in the light emitting layer, and also a layer that suppresses holes from penetrating to the cathode side.

  The material used for the block layer is not particularly limited as long as it is a material that can receive electrons from the electron transport layer and pass the electrons to the light emitting layer, and a general electron transport material can be used. For example, the following materials can be mentioned. Triazole derivatives, oxazole derivatives, oxadiazol derivatives, fluorenone derivatives, anthraquinodimethane derivatives, anthrone derivatives, diphenylquinone derivatives, thiopyrandioxide derivatives, carbodiimide derivatives, fluorenylidenemethane derivatives, distyrylpyrazine derivatives , Metal complexes of heterocyclic tetracarboxylic anhydrides such as naphthaleneperylene, phthalocyanine derivatives, 8-quinolinol derivatives and metal complexes having metal phthalocyanine, benzoxazole and benzothiazol as ligands Polymers such as complexes, aniline copolymers, conductive polymer oligomers such as thiophene oligomers and polythiophenes, polythiophene derivatives, polyphenylene derivatives, polyphenylene vinylene derivatives, polyfluorene derivatives, etc. It can be mentioned. These may be used individually by 1 type and may use 2 or more types together.

6) Electron transport layer In the present invention, an electron transport layer containing an electron transport material can be provided.
The electron transport material is not limited as long as it has either a function of transporting electrons or a function of blocking holes injected from the anode, and is mentioned when explaining the block layer. A suitable electron transport material can be used.
The thickness of the electron transport layer is preferably 10 nm to 200 nm, and more preferably 20 nm to 80 nm.

  If the thickness exceeds 200 nm, the driving voltage may increase, and if it is less than 10 nm, the light emitting device may be short-circuited.

7) Electron Injection Layer In the present invention, an electron injection layer can be provided between the electron transport layer and the cathode.
The electron injection layer is a layer that facilitates injection of electrons from the cathode into the electron transport layer. Specifically, lithium salts such as lithium fluoride, lithium chloride, and lithium bromide, sodium fluoride, sodium chloride, fluoride An alkali metal salt such as cesium, an insulating metal oxide such as lithium oxide, aluminum oxide, indium oxide, or magnesium oxide can be preferably used.
The thickness of the electron injection layer is preferably 0.1 nm to 5 nm.

8) Formation method of organic compound layer The organic compound layer is formed by a dry film forming method such as vapor deposition or sputtering, dipping, spin coating, dip coating, casting, die coating, or roll coating. The film can be suitably formed by any of wet film forming methods such as a coat method, a bar coat method, or a gravure coat method.
Of these, the dry method is preferred from the viewpoint of luminous efficiency and durability.

Next, the substrate and electrodes used in the organic electroluminescence device of the present invention will be described.
9) Substrate As the material of the substrate used in the present invention, both the first substrate and the second substrate are preferably materials that do not transmit moisture or materials with extremely low moisture permeability, and light emitted from the organic compound layer. A material that does not scatter or attenuate the light is preferable. Specific examples include, for example, YSZ (zirconia stabilized yttrium), inorganic materials such as glass, polyethylene terephthalate, polybutylene terephthalate, polyester such as polyethylene naphthalate, polystyrene, polycarbonate, Examples thereof include organic materials such as polyethersulfone, polyarylate, allyl diglycol carbonate, polyimide, polycycloolefin, norbornene resin, and synthetic resin such as poly (chlorotrifluoroethylene).
In the case of the organic material, it is preferable that the organic material is excellent in heat resistance, dimensional stability, solvent resistance, electrical insulation, workability, low air permeability, low moisture absorption, and the like. Among these, when the material of the transparent electrode is indium tin oxide (ITO) suitably used as the material of the transparent electrode, a material having a small difference in lattice constant from the indium tin oxide (ITO) is used. preferable. These materials may be used alone or in combination of two or more.

  There is no restriction | limiting in particular about the shape of a board | substrate, a structure, a magnitude | size, It can select suitably according to the use, purpose, etc. of a light emitting element. Generally, the shape is a plate shape. The structure may be a single layer structure, a laminated structure, may be formed of a single member, or may be formed of two or more members.

  The substrate may be colorless and transparent, or may be colored and transparent, but is preferably colorless and transparent in that it does not scatter or attenuate light emitted from the light emitting layer.

The substrate is preferably provided with a moisture permeation preventing layer (gas barrier layer) on the front surface or the back surface (on the transparent electrode side). As the material for the moisture permeation preventive layer (gas barrier layer), inorganic materials such as silicon nitride and silicon oxide are preferably used. The moisture permeation preventing layer (gas barrier layer) can be formed by, for example, a high frequency sputtering method.
The substrate may be further provided with a hard coat layer, an undercoat layer, and the like as required.

10) Anode As the anode used in the present invention, it is usually sufficient to have a function as an anode for supplying holes to the organic compound layer, and the shape, structure, size and the like are not particularly limited. Depending on the use and purpose of the light-emitting element, it can be appropriately selected from known electrodes.

  As a material for the anode, for example, a metal, an alloy, a metal oxide, an organic conductive compound, or a mixture thereof can be preferably cited. A material having a work function of 4.0 eV or more is preferable. Specific examples include semiconducting metals such as tin oxide doped with antimony and fluorine (ATO, FTO), tin oxide, zinc oxide, indium oxide, indium tin oxide (ITO), and zinc indium oxide (IZO). Metals such as oxides, gold, silver, chromium and nickel, and mixtures or laminates of these metals and conductive metal oxides, inorganic conductive materials such as copper iodide and copper sulfide, polyaniline, polythiophene, polypyrrole Organic conductive materials such as copper, and laminates of these with ITO.

  The anode is, for example, a printing method, a wet method such as a coating method, a physical method such as a vacuum deposition method, a sputtering method, or an ion plating method, or a chemical method such as a CVD or a plasma CVD method. Can be formed on the substrate in accordance with a method appropriately selected in consideration of suitability. For example, when ITO is selected as the anode material, the anode can be formed according to a direct current or high frequency sputtering method, a vacuum deposition method, an ion plating method, or the like. Moreover, when selecting an organic electroconductive compound as a material of an anode, it can carry out according to the wet film forming method.

  There is no restriction | limiting in particular as a formation position in the said light emitting element of an anode, Although it can select suitably according to the use and objective of this light emitting element, It is preferable to form on the said board | substrate. In this case, the anode may be formed on the entire one surface of the substrate or a part thereof.

  The patterning of the anode may be performed by chemical etching such as photolithography, or may be performed by physical etching using a laser or the like, or may be performed by vacuum deposition or sputtering by overlapping a mask. Etc., or may be performed by a lift-off method or a printing method.

The thickness of the anode can be appropriately selected depending on the material and cannot be generally defined, but is usually 10 nm to 50 μm, and preferably 50 nm to 20 μm.
The resistance value of the anode is preferably 10 ³ Ω / □ or less, and more preferably 10 ² Ω / □ or less.
The anode may be colorless and transparent or colored and transparent. In order to extract light emitted from the anode side, the transmittance is preferably 60% or more, and more preferably 70% or more. This transmittance can be measured according to a known method using a spectrophotometer.

  The anode is described in detail in the book “New Development of Transparent Electrode Film”, published by CMC (1999), supervised by Yutaka Sawada, and these can be applied to the present invention. When using a plastic substrate having low heat resistance, an anode formed using ITO or IZO at a low temperature of 150 ° C. or lower is preferable.

11) Cathode As a cathode that can be used in the present invention, it suffices as long as it normally has a function as a cathode for injecting electrons into the organic compound layer, and the shape, structure, size and the like are not particularly limited. However, it can be appropriately selected from known electrodes according to the use and purpose of the light-emitting element.

  Examples of the material for the cathode include metals, alloys, metal oxides, electrically conductive compounds, mixtures thereof, and the like, and those having a work function of 4.5 eV or less are preferable. Specific examples include alkali metals (for example, Li, Na, K, or Cs), alkaline earth metals (for example, Mg, Ca, etc.), gold, silver, lead, aluminum, sodium-potassium alloys, lithium-aluminum alloys, Examples thereof include magnesium-silver alloys, rare earth metals such as indium and ytterbium. These may be used alone, but from the viewpoint of achieving both stability and electron injection properties, two or more of them can be suitably used in combination.

  Among these, alkali metals and alkalinity metals are preferable from the viewpoint of electron injection properties, and materials mainly composed of aluminum are preferable from the viewpoint of excellent storage stability. The material mainly composed of aluminum is aluminum alone, or an alloy or mixture of aluminum and 0.01% by mass to 10% by mass of alkali metal or alkaline earth metal (for example, lithium-aluminum alloy, magnesium-aluminum alloy, etc. ).

  The cathode materials are described in detail in JP-A-2-15595 and JP-A-5-121172, and these can be applied to the present invention.

  There is no restriction | limiting in particular in the formation method of a cathode, It can carry out according to a well-known method. For example, a printing method, a wet method such as a coating method, a physical method such as a vacuum deposition method, a sputtering method, or an ion plating method, a chemical method such as a CVD method or a plasma CVD method, etc. It can be formed on the substrate according to a method appropriately selected in consideration of suitability. For example, when a metal or the like is selected as the material of the cathode, one or more of them can be simultaneously or sequentially performed according to a sputtering method or the like.

  The patterning of the cathode may be performed by chemical etching such as photolithography, or may be performed by physical etching using a laser or the like, or vacuum deposition or sputtering is performed with a mask overlapped. It may be performed by a lift-off method or a printing method.

There is no restriction | limiting in particular as a formation position in the organic electroluminescent element of a cathode, Although it can select suitably according to the use and objective of this light emitting element, forming in an organic compound layer is preferable. In this case, the cathode may be formed on the entire organic compound layer or a part thereof.
Further, a dielectric layer made of the alkali metal or the alkaline earth metal fluoride may be inserted between the cathode and the organic compound layer with a thickness of 0.1 nm to 5 nm.
The dielectric layer can be formed by, for example, a vacuum deposition method, a sputtering method, or an ion plating method.

The thickness of the cathode can be appropriately selected depending on the material and cannot be generally defined, but is usually 10 nm to 5 μm, and preferably 50 nm to 1 μm.
The cathode may be transparent or opaque. The transparent cathode can be formed by forming the cathode material into a thin film with a thickness of 1 nm to 10 nm and further laminating the transparent conductive material such as ITO or IZO.

2. Inorganic electroluminescent element An inorganic electroluminescent element includes first and second insulating films made of an oxide having a high dielectric constant disposed between electrodes, and a light emitting layer made of sulfide sandwiched between the insulating films. Includes functional layer. As the insulating layer, materials such as tantalum pentoxide (Ta ₂ O ₅ ), titanium oxide (TiO ₂ ), yttrium oxide (Y ₂ O ₃ ), barium titanate (BaTiO ₃ ), strontium titanate (SrTiO ₃ ), etc. Can be used. For the light emitting layer, materials such as zinc sulfide (ZnS), calcium sulfide (CaS), strontium sulfide (SrS), barium thioaluminate (BaAl ₂ S ₄ ) are used as the base material of the light emitting layer, and manganese is used as the light emitting center. A transition metal element such as (Mn) or a rare earth element such as europium (Eu), cerium (Ce), or terbium (Tb) can be used.

3. Photoelectric conversion element The photoelectric conversion element includes a semiconductor layer having a pn junction or a pin junction between electrodes, and a functional layer such as an X-ray photoconductor layer that generates charges by X-ray irradiation, and includes a photodetector, solar cell, and X-ray detection. It can be used for containers. The material is appropriately selected according to each application. Amorofas silicon (a-Si), polycrystalline silicon, amorofas selenium (a-Se), cadmium sulfide (CdS), cadmium telluride (CdTe), zinc oxide (ZnO) ), Lead oxide (PbO), lead iodide (PbI ₂ ), Bi ₁₂ (Ge, Si) O ₂₀ , or the like can be used. These can be doped with impurities as needed to control the conductivity type.

4). Piezoelectric transducers Piezoelectric transducers include functional layers such as layers that generate strain between electrodes or generate voltage due to pressure or strain, and are used for pressure sensors, acceleration sensors, ultrasonic oscillators, actuators, etc. Available. As a material of the piezoelectric layer, lead zirconate titanate (PZT), lead titanate (PbTiO ₃ ), lithium niobate (LiNbO ₃ ), lithium tantalate (LiTaO ₃ ), lithium tetraborate (Li ₂ B ₄₎ O ₇ ), aluminum nitride (AlN), quartz (SiO ₂ ), polyvinylidene fluoride (PVDF), or the like can be used.
Examples of the gas detection layer include an n-type semiconductor layer whose resistance value changes in the gas between the electrodes. As a material of the n-type semiconductor layer, tin oxide (SnO ₂ ), zinc oxide (ZnO), or the like can be used. A composite in which metal nanoparticles such as Ag are supported in pores of porous silicon oxide (SiO ₂ ) can also be used.

4). Element Structure The structure of the element in the present invention will be described with reference to the drawings.
FIG. 1 is a schematic diagram of a functional element of the present invention. The substrate has a striped first electrode and a second electrode terminal at the end. The stripe gap at the end of the stripe-shaped first electrode is filled with a planarization insulating layer. A functional layer is provided between the planar second electrode and the first electrode.
A first electrode 2 and a second electrode terminal 3 are provided on the substrate 1. These electrodes are preferably made of the same material. The material may be a transparent conductive film such as ITO or an opaque metal electrode such as Al. On the substrate 1 including these electrodes, a planarization insulating layer 5 is disposed at the end portion in the longitudinal direction of the stripe of the first electrode 2 so as to cross the first electrode 2. A planar second electrode 4 is disposed on a region sandwiched between the planarization insulating layers 5 disposed at the substantially end portions. The second electrode 4 and the second electrode terminal 3 are directly electrically connected. Although not shown, a functional layer is provided between the first electrode 2 and the planar second electrode 4 sandwiched between the planarization insulating layers 5 disposed at the ends in the longitudinal direction of the stripes.

FIG. 2 is a schematic view of a cross section of an end portion having a planarizing insulating layer of the functional element of the present invention.
A planarization insulating layer 5 is disposed on the substrate 1 including the first electrode 2 and the second electrode terminal 3 formed in a stripe shape. Here, the planarization insulating layer 5 is formed so as to fill a gap between the first electrode 2 and the second electrode terminal 3, and covers the first electrode 2 and a part of the second electrode terminal 3. Is formed. Further, the functional layer 6 and the second electrode 4 are sequentially formed.

FIG. 3 is a schematic view of a cross section of an end portion that does not have a planarization insulating layer, and shows a comparative element structure.
A functional layer 6 and a second electrode 4 are sequentially formed on a substrate 1 including a first electrode 2 and a second electrode terminal 3 formed in a stripe shape. In this case, in the step portion formed in the gap between the first electrode 2 and the second electrode terminal 3, the first electrode 2 and the second electrode terminal 3 and the second electrode cannot be sufficiently insulated, and a short circuit is caused. Cause.

(Flattened insulation layer)
<Function>
In the planarization insulating layer according to the present invention, the step of the gap between the stripe electrodes is filled, the upper surface of the electrode and the upper surface of the portion where no electrode is formed form substantially the same plane, and the functional layer and the second electrode installed thereon Is a layer for enabling a flat layer to be formed. As a result, the function of the functional layer is stabilized and the occurrence of the disconnection failure of the second electrode is improved.
Preferably, the planarization insulating layer not only fills the gap in the gap between the stripe electrodes, but also forms an insulating layer between the stripe electrode and the functional layer. For this purpose, it is preferable to install the planarization insulating layer thicker than the stripe electrode.

<Material>
As a material used for the planarization insulating layer, a conventionally known material used as an insulating material can be used. Preferably, it is a photosensitive resin or a thermosetting resin, melted or dissolved in a solvent and filled, and then cured by ultraviolet light, visible light or heating to form a film having a high physical strength.
<Specific examples of photosensitive resin or thermosetting resin>
The photosensitive resin or thermosetting resin is not particularly limited, and an acrylic resin or an epoxy resin can be used. Among these, an epoxy resin is preferable from the viewpoint of moisture prevention function.
<Production method>
The method for manufacturing the planarization insulating layer is not particularly limited, and examples thereof include a method of obtaining a predetermined pattern by photolithography after applying a resin, or a method of directly obtaining a predetermined pattern using a dispenser.
<Layer thickness>
The planarization insulating layer is preferably thicker than the first electrode. If it is thinner than this, the first electrode and the second electrode may be short-circuited at the pattern edge portion of the first electrode.

(Inorganic insulating layer)
In the functional element of the present invention, an inorganic insulating layer may be further provided between the planarizing insulating layer and the functional layer.
The inorganic insulating layer used in the present invention is a layer that prevents deterioration due to intrusion of gas such as moisture and oxygen.
As the material for the inorganic insulating layer used in the present invention, silicon nitride, silicon oxynitride, silicon oxide, and silicon carbide are preferably used.
The inorganic insulating layer used in the present invention can be formed by a CVD method, an ion plating method, a sputtering method, or a vapor deposition method.
The thickness of the inorganic insulating layer used in the present invention is preferably 0.01 μm to 10 μm. If it is thinner than 0.01 μm, the insulating function and the moisture and gas preventing function are insufficient, which is not preferable. On the other hand, if it is thicker than 10 μm, it takes a long time to form a film, which is not preferable in the process. In addition, the film stress may increase, causing film peeling and the like. A thicker film can be obtained by repeating the film formation a plurality of times.

(Resin sealing layer)
The resin sealing layer used in the present invention is a layer that fills the gas phase space between the inorganic film layer and the second substrate. Accordingly, the present invention is characterized in that the gap between the inorganic film layer and the second substrate is entirely filled with resin and does not have a gas phase space.
<Material>
The resin material for the resin sealing layer is not particularly limited, and an acrylic resin, an epoxy resin, a fluorine resin, a silicon resin, a rubber resin, an ester resin, or the like can be used. An epoxy resin is preferable from the viewpoint of the prevention function. Among the epoxy resins, a thermosetting epoxy resin or a photocurable epoxy resin is preferable.
<Production method>
The method for producing the resin sealing layer is not particularly limited, and examples thereof include a method of applying a resin solution, a method of pressure bonding or thermocompression bonding of a resin sheet, and a method of dry polymerization by vapor deposition or sputtering.
<Film thickness>
The thickness of the resin sealing layer is preferably 1 μm or more and 1 mm or less. More preferably, they are 5 micrometers or more and 100 micrometers or less, Most preferably, they are 10 micrometers or more and 50 micrometers or less. If it is thinner than this, the inorganic film may be damaged when the second substrate is mounted. On the other hand, if the thickness is larger than this, the thickness of the electroluminescent element itself is increased, and the thin film property that is characteristic of the organic electroluminescent element is impaired.

(Sealing adhesive)
The organic electroluminescent element in the present invention is sandwiched between two substrates, and the peripheral edge of the substrate is sealed with a sealing adhesive having excellent moisture resistance.
The sealing adhesive in the present invention has a function of preventing intrusion of moisture and oxygen from the end portion.
The organic electroluminescent device of the present invention is sandwiched between two substrates impermeable to moisture and gas, and has no gas phase space inside, so that intrusion of gas such as moisture and oxygen from the outside Is kept extremely low, but can be made more perfect by sealing the end with a sealing adhesive having excellent moisture resistance.

<Material>
As the material of the sealing adhesive, the same material as that used for the resin sealing layer can be used. Among these, epoxy adhesives are preferable from the viewpoint of moisture prevention, and photocurable epoxy adhesives are particularly preferable.

It is also preferable to add a filler to the above material.
The filler added to the sealant is preferably an inorganic material such as SiO ₂ , SiO (silicon oxide), SiON (silicon oxynitride) or SiN (silicon nitride). Addition of the filler increases the viscosity of the sealant, improves processing suitability, and improves moisture resistance.

<Drying agent>
The sealing adhesive may contain a desiccant. As the desiccant, barium oxide, calcium oxide, or strontium oxide is preferable.
The amount of the desiccant added to the sealing adhesive is preferably 0.01% by mass or more and 20% by mass or less, and more preferably 0.05% by mass or more and 15% by mass or less. If the amount is less than this, the effect of adding the desiccant is diminished. On the other hand, when it is more than this, it becomes difficult to uniformly disperse the desiccant in the sealing adhesive, which is not preferable.
<Prescription of sealing adhesive>
・ Polymer composition, concentration,
It does not specifically limit as a sealing adhesive agent, The said thing can be used. For example, XNR5516 manufactured by Nagase Chemtech Co., Ltd. can be cited as a photo-curable epoxy adhesive. What is necessary is just to add and disperse | distribute the said desiccant directly there.
-Thickness The coating thickness of the sealing adhesive is preferably 1 μm or more and 1 mm or less. If it is thinner than this, the sealing adhesive cannot be applied uniformly, which is not preferable. On the other hand, if it is thicker than this, the route through which moisture invades becomes wide, which is not preferable.
<Sealing method>
In the present invention, a functional element can be obtained by applying an arbitrary amount of the sealing adhesive containing the desiccant with a dispenser or the like, and stacking and curing the second substrate after application.

  The present invention will be described more specifically with reference to the following examples. However, the present invention is not limited to the examples described below.

Example 1
(Formation of stripe electrode)
On a non-alkali substrate, a transparent conductive film, for example, a lower electrode made of ITO was formed to a thickness of 200 nm by a sputtering method, and formed into stripes having a width of 50 μm and an interval of 50 μm by wet etching.

(Formation of planarization insulating layer)
Next, after applying photosensitive polyimide to the entire surface by spin coating, an insulating layer having a width of 10 mm is formed by photolithography so as to be orthogonal to the stripe electrode between the external connection terminal portion of the stripe-shaped lower electrode and the functional region. Formed.

(Formation of organic EL layer)
Next, an organic EL layer was deposited using an evaporation mask having an opening at a predetermined position.
In this case, the organic EL layer has a layer structure and a thickness of, for example, a hole injection layer made of 30 nm MTDATA [4,4 ′, 4 ″ -tris (3-methylphenylphenylamino) triferamine], 20 nm Hole transport layer made of α-NPD (N, N′-dinaphthyl-N, N′-diphenyl- [1,1′-biphenyl] 4,4′-diamine), 30 nm host Alq3 (Tris (8-hydroxy Light-emitting layer doped with luminescent material t (npa) py (1,3,6,8-tetra [N- (naphthyl) -N-phenylamino] pyrene) on quinoninate) aluminum), electron transport composed of 20 nm Alq3 Layers were formed by sequential vacuum evaporation.
Next, a display using the organic EL element of Example 1 of the present invention is formed by forming an upper electrode made of Al so as to cover the organic EL layer using an upper electrode vapor deposition mask having an opening at a predetermined position. The device was completed.

(Performance and effect)
In the display element using the organic EL element of Example 1 of the present invention, holes are injected from the lower electrode into the organic EL layer by applying a voltage between the lower electrode and the upper electrode, and from the upper electrode. Electrons were injected into the organic EL layer, and the injected holes were transported to the light emitting layer by the hole transport layer, and the injected electrons were transported to the light emitting layer by the electron transport layer.
The holes and electrons thus transported to the light-emitting layer recombine in the light-emitting layer, so that light was emitted, and the emitted light was extracted from the translucent lower electrode side.

  As described above, in the first embodiment of the present invention, the upper electrode is provided so as to cross the stripe-like lower electrode, and an insulating layer is provided between the external connection terminal of the stripe-like lower electrode and the functional region for planarization. Depending on the thickness and shape of the stripe-shaped lower electrode, even if the upper electrode that is crossed in the functional region is cut, the upper electrode remains connected on the planarized insulating layer, so that the disconnection is eliminated. I was able to. Further, since there is no polyimide as a resin on the short side of the striped electrode in the functional region, it was possible to greatly suppress light emission deterioration due to gas generated from the resin.

Example 2
(Formation of stripe electrode)
A lower electrode made of an ITO transparent conductive film was formed on an alkali-free glass substrate to a thickness of 200 nm by a sputtering method, and stripe electrodes having a width of 50 μm and an interval of 50 μm were formed by wet etching.

(Formation of planarization insulating layer)
Colloidal silica (manufactured by Fuso Chemical Industry Co., Ltd .; PL-1) was applied to both ends in the long side direction of the stripe electrode with a width of 10 mm so as to be orthogonal to the stripe electrode and dried. Next, heat treatment was performed at 500 ° C. for 1 hour to form a smoothing insulating layer.

(Formation of inorganic EL layer)
A first insulating film made of tantalum pentoxide (Ta ₂ O ₅ ) is held at a substrate temperature of 200 ° C. and a pressure of 1 Pa inside so as to cover a part of the substrate, the stripe electrode, and the smoothing insulating layer. Then, sputtering was performed at a sputtering rate of 0.2 nm / sec at a high frequency power of 1 kW in an argon mixed gas atmosphere containing oxygen to form a film with a thickness of 200 nm. Next, a light emitting layer made of zinc sulfide (ZnS) to which 3 mol% of manganese (Mn) was added was similarly subjected to high-frequency sputtering in an argon mixed gas atmosphere containing hydrogen sulfide (H ₂ S) at a substrate temperature of 350 ° C. The film was formed with a film thickness of 400 nm. Next, a second insulating film made of tantalum pentoxide (Ta ₂ O ₅ ) was formed to a thickness of 200 nm in the same manner as the first insulating layer.
After the above layers were deposited on the substrate, heat treatment was performed at 400 ° C. for 1 hour in a vacuum of 10 ⁻⁴ Pa.
Furthermore, an electrode made of aluminum was formed thereon with a film thickness of 50 nm by vacuum vapor deposition to produce an inorganic EL element.

It is a conceptual diagram of the functional element which concerns on embodiment of this invention. It is a conceptual diagram of the stripe electrode edge part of the functional element which concerns on embodiment of this invention. It is a conceptual diagram of the stripe electrode edge part of the functional element which concerns on a comparison form.

Explanation of symbols

1. Substrate 2. First electrode 3. Second electrode terminal 4. Second electrode 5. 5. Planarization insulating layer Functional layer

Claims (7)

A first electrode in which a plurality of stripe electrodes are arranged in parallel on a substrate; a second electrode terminal in which the plurality of stripe electrodes are arranged on the same plane as the first electrode in parallel; arranged opposite to the first electrode ; A second electrode connected to a terminal of the second electrode, and a functional element having a functional layer sandwiched between the first electrode and the second electrode,
In the both end portions of the first stripe electrode longitudinally, the disposed between the region corresponding to the functional area of the terminal portion and the first electrode on the first electrode, wherein the gap between the stripe first A planarization insulating layer that fills thicker than one electrode and covers and planarizes a part of the first electrode and the second electrode terminal ;
The second electrode is arranged in a planar shape having a uniform thickness so as to cover the region corresponding to the functional region on the first electrode and the planarization insulating layer, and is connected to the second electrode terminal.
The functional element, wherein the functional layer on the planarization insulating layer is insulated from the first electrode at an end in the longitudinal direction.   The functional element according to claim 1, wherein the functional layer forms a continuous layer at an end in the longitudinal direction.   The functional element according to claim 1, wherein the planarization insulating layer is formed of a photosensitive resin or a thermosetting resin.   The functional element according to claim 1, further comprising an inorganic insulating layer between the planarizing insulating layer and the functional layer.   The functional element according to claim 1, wherein at least one of the functional layers is a light emitting layer.   The functional element according to claim 5, wherein the functional element is an organic electroluminescent element.   The functional element according to claim 5, wherein the functional element is an inorganic electroluminescent element.

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